50 results on '"Branch O"'
Search Results
2. Pf7: an open dataset of Plasmodium falciparum genome variation in 20,000 worldwide samples
- Author
-
Hamid, M.M.A., Abdelraheem, M.H., Acheampong, D.O., Ahouidi, A., Ali, M, Almagro-Garcia, J., Amambua-Ngwa, A., Amaratunga, C., Amenga-Etego, L., Andagalu, B., Anderson, T., Andrianaranjaka, V., Aniebo, I., Aninagyei, E., Ansah, F., Ansah, P.O., Apinjoh, T., Arnaldo, P., Ashley, E., Auburn, S., Awandare, G.A., Ba, H., Baraka, V., Barry, A., Bejon, P., Bertin, G.I., Boni, M.F., Borrmann, S., Bousema, T., Bouyou-Akotet, M., Branch, O., Bull, P.C., Cheah, H., Chindavongsa, K., Chookajorn, T., Chotivanich, K., Claessens, A., Conway, D.J., Corredor, V., Courtier, E., Craig, A., D'Alessandro, U., Dama, S., Day, N., Denis, B., Dhorda, M., Diakite, M., Djimde, A., Dolecek, C., Dondorp, A., Doumbia, S., Drakeley, C., Drury, E., Duffy, P., Echeverry, D.F., Egwang, T.G., Enosse, S.M.M., Erko, B., Fairhurst, R.M., Faiz, A., Fanello, C.A., Fleharty, M., Forbes, M., Fukuda, M., Gamboa, D., Ghansah, A., Golassa, L., Goncalves, S., Harrison, G.L.A., Healy, Sara A., Hendry, J.A., Hernandez-Koutoucheva, A., Hien, T.T., Hill, C.A., Hombhanje, F., Hott, A., Htut, Y., Hussein, M., Imwong, M., Ishengoma, D., Jackson, S.A., Jacob, C.G., Jeans, J., Johnson, K.J., Kamaliddin, C., Kamau, E., Keatley, J., Kochakarn, T., Konate, D.S., Konaté, A., Kone, A., Kwiatkowski, D.P., Kyaw, M.P., Kyle, D., Lawniczak, M., Lee, S.K., Lemnge, M., Lim, P., Lon, C., Yavo, W., Pluijm, R.W. van der, Hamid, M.M.A., Abdelraheem, M.H., Acheampong, D.O., Ahouidi, A., Ali, M, Almagro-Garcia, J., Amambua-Ngwa, A., Amaratunga, C., Amenga-Etego, L., Andagalu, B., Anderson, T., Andrianaranjaka, V., Aniebo, I., Aninagyei, E., Ansah, F., Ansah, P.O., Apinjoh, T., Arnaldo, P., Ashley, E., Auburn, S., Awandare, G.A., Ba, H., Baraka, V., Barry, A., Bejon, P., Bertin, G.I., Boni, M.F., Borrmann, S., Bousema, T., Bouyou-Akotet, M., Branch, O., Bull, P.C., Cheah, H., Chindavongsa, K., Chookajorn, T., Chotivanich, K., Claessens, A., Conway, D.J., Corredor, V., Courtier, E., Craig, A., D'Alessandro, U., Dama, S., Day, N., Denis, B., Dhorda, M., Diakite, M., Djimde, A., Dolecek, C., Dondorp, A., Doumbia, S., Drakeley, C., Drury, E., Duffy, P., Echeverry, D.F., Egwang, T.G., Enosse, S.M.M., Erko, B., Fairhurst, R.M., Faiz, A., Fanello, C.A., Fleharty, M., Forbes, M., Fukuda, M., Gamboa, D., Ghansah, A., Golassa, L., Goncalves, S., Harrison, G.L.A., Healy, Sara A., Hendry, J.A., Hernandez-Koutoucheva, A., Hien, T.T., Hill, C.A., Hombhanje, F., Hott, A., Htut, Y., Hussein, M., Imwong, M., Ishengoma, D., Jackson, S.A., Jacob, C.G., Jeans, J., Johnson, K.J., Kamaliddin, C., Kamau, E., Keatley, J., Kochakarn, T., Konate, D.S., Konaté, A., Kone, A., Kwiatkowski, D.P., Kyaw, M.P., Kyle, D., Lawniczak, M., Lee, S.K., Lemnge, M., Lim, P., Lon, C., Yavo, W., and Pluijm, R.W. van der
- Abstract
Item does not contain fulltext, We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network. It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented. For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations. We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent. We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines. Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website.
- Published
- 2023
3. Guidelines for clinical diagnosis and treatment of urinary tract infection in kidney transplant recipients in China
- Author
-
Branch of Organ Transplantation of Chinese Medical Association
- Subjects
kidney transplantation ,urinary tract infection ,drug resistant bacteria ,antibiotic ,simple cystitis ,pyelonephritis ,asymptomatic bacteriuria ,gram negative bacteria ,Medicine - Abstract
Urinary tract infection is the most common infectious complication after kidney transplantation. To further reduce the incidence of urinary tract infection after kidney transplantation, improve the diagnosis and treatment level of urinary tract infection after kidney transplantation in China, prevent the development of bacterial drug resistance and ensure the safety and effectiveness of drug use, Branch of Organ Transplantation of Chinese Medical Association organized experts in the fields of kidney transplantation and infectious diseases to consider clinical status of urinary tract infection after kidney transplantation in China, refer to “Diagnosis and Treatment of Urological and Andrological Diseases in China (2022 edition)” and “Urinary Tract Infection in Solid Organ Transplant Recipients in American Society of Transplantation Practical Guidelines for Infectious Diseases (2019 edition) ”, and formulate “Guidelines for Clinical Diagnosis and Treatment of Urinary Tract Infection in Kidney Transplant Recipients in China” from the perspectives of clinical classification and definition, epidemiology and etiology, diagnosis and treatment of urinary tract infection after kidney transplantation, respectively.
- Published
- 2024
- Full Text
- View/download PDF
4. High-Resolution Climate Predictions and Short-Range Forecasts to Improve the Process Understanding and the Representation of Land-Surface Interactions in the WRF Model in Southwest Germany (WRFCLIM)
- Author
-
Warrach-Sagi, K., primary, Bauer, Hans-Stefan, additional, Schwitalla, T., additional, Milovac, J., additional, Branch, O., additional, and Wulfmeyer, V., additional
- Published
- 2014
- Full Text
- View/download PDF
5. An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples
- Author
-
Ahouidi, A., Ali, M, Almagro-Garcia, J., Amambua-Ngwa, A., Amaratunga, C., Amato, R., Amenga-Etego, L., Andagalu, B., Anderson, T.J., Andrianaranjaka, V., Apinjoh, T., Ariani, C., Ashley, E.A., Auburn, S., Awandare, G.A., Ba, H., Baraka, V., Barry, A.E., Bejon, P., Bertin, G.I., Boni, M.F., Borrmann, S., Bousema, T., Branch, O., Bull, P.C., Busby, G.B.J., Chookajorn, T., Chotivanich, K., Claessens, A., Conway, D., Craig, A., D'Alessandro, U., Dama, S., Day, N.P., Denis, B., Diakite, M., Djimdé, A., Dolecek, C., Dondorp, A.M., Drakeley, C., Drury, E., Duffy, P., Echeverry, D.F., Egwang, T.G., Erko, B., Fairhurst, R.M., Faiz, A., Fanello, C.A., Fukuda, M.M., Gamboa, D., Ghansah, A., Golassa, L., Goncalves, S., Hamilton, W.L., Harrison, G.L.A., Hart, L. 't, Henrichs, C., Hien, T.T., Hill, C.A., Hodgson, A., Hubbart, C., Imwong, M., Ishengoma, D.S., Jackson, S.A., Jacob, C.G., Jeffery, B., Jeffreys, A.E., Johnson, K.J., Jyothi, D., Kamaliddin, C., Kamau, E., Kekre, M., Kluczynski, K., Kochakarn, T., Konaté, A., Kwiatkowski, D.P., Kyaw, M.P., Lim, P., Lon, C., Loua, K.M., Maïga-Ascofaré, O., Malangone, C., Manske, M., Marfurt, J., Marsh, K., Mayxay, M., Miles, A., Miotto, O., Mobegi, V., Mokuolu, O.A., Montgomery, J., Mueller, I., Newton, P.N., Nguyen, T., Nguyen, T.N.D., Noedl, H., Nosten, F., Noviyanti, R., Nzila, A., Ochola-Oyier, L.I., and MalariaGEN
- Subjects
0301 basic medicine ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,lnfectious Diseases and Global Health Radboud Institute for Health Sciences [Radboudumc 4] ,030231 tropical medicine ,parasitic diseases ,Medicine (miscellaneous) ,General Biochemistry, Genetics and Molecular Biology ,3. Good health - Abstract
Contains fulltext : 238195.pdf (Publisher’s version ) (Open Access) MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.
- Published
- 2021
6. An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples.
- Author
-
MalariaGEN, Ahouidi, A, Ali, M, Almagro-Garcia, J, Amambua-Ngwa, A, Amaratunga, C, Amato, R, Amenga-Etego, L, Andagalu, B, Anderson, TJC, Andrianaranjaka, V, Apinjoh, T, Ariani, C, Ashley, EA, Auburn, S, Awandare, GA, Ba, H, Baraka, V, Barry, Alyssa, Bejon, P, Bertin, GI, Boni, MF, Borrmann, S, Bousema, T, Branch, O, Bull, PC, Busby, GBJ, Chookajorn, T, Chotivanich, K, Claessens, A, Conway, D, Craig, A, D'Alessandro, U, Dama, S, Day, NP, Denis, B, Diakite, M, Djimdé, A, Dolecek, C, Dondorp, AM, Drakeley, C, Drury, E, Duffy, P, Echeverry, DF, Egwang, TG, Erko, B, Fairhurst, RM, Faiz, A, Fanello, CA, Fukuda, MM, Gamboa, D, Ghansah, A, Golassa, L, Goncalves, S, Hamilton, WL, Harrison, GLA, Hart, L, Henrichs, C, Hien, TT, Hill, CA, Hodgson, A, Hubbart, C, Imwong, M, Ishengoma, DS, Jackson, SA, Jacob, CG, Jeffery, B, Jeffreys, AE, Johnson, KJ, Jyothi, D, Kamaliddin, C, Kamau, E, Kekre, M, Kluczynski, K, Kochakarn, T, Konaté, A, Kwiatkowski, DP, Kyaw, MP, Lim, P, Lon, C, Loua, KM, Maïga-Ascofaré, O, Malangone, C, Manske, M, Marfurt, J, Marsh, K, Mayxay, M, Miles, A, Miotto, O, Mobegi, V, Mokuolu, OA, Montgomery, J, Mueller, I, Newton, PN, Nguyen, T, Nguyen, T-N, Noedl, H, Nosten, F, Noviyanti, R, Nzila, A, Ochola-Oyier, LI, Ocholla, H, Oduro, A, Omedo, I, Onyamboko, MA, Ouedraogo, J-B, Oyebola, K, Pearson, RD, Peshu, N, Phyo, AP, Plowe, CV, Price, RN, Pukrittayakamee, S, Randrianarivelojosia, M, Rayner, JC, Ringwald, P, Rockett, KA, Rowlands, K, Ruiz, L, Saunders, D, Shayo, A, Siba, P, Simpson, VJ, Stalker, J, Su, X-Z, Sutherland, C, Takala-Harrison, S, Tavul, L, Thathy, V, Tshefu, A, Verra, F, Vinetz, J, Wellems, TE, Wendler, J, White, NJ, Wright, I, Yavo, W, Ye, H, MalariaGEN, Ahouidi, A, Ali, M, Almagro-Garcia, J, Amambua-Ngwa, A, Amaratunga, C, Amato, R, Amenga-Etego, L, Andagalu, B, Anderson, TJC, Andrianaranjaka, V, Apinjoh, T, Ariani, C, Ashley, EA, Auburn, S, Awandare, GA, Ba, H, Baraka, V, Barry, Alyssa, Bejon, P, Bertin, GI, Boni, MF, Borrmann, S, Bousema, T, Branch, O, Bull, PC, Busby, GBJ, Chookajorn, T, Chotivanich, K, Claessens, A, Conway, D, Craig, A, D'Alessandro, U, Dama, S, Day, NP, Denis, B, Diakite, M, Djimdé, A, Dolecek, C, Dondorp, AM, Drakeley, C, Drury, E, Duffy, P, Echeverry, DF, Egwang, TG, Erko, B, Fairhurst, RM, Faiz, A, Fanello, CA, Fukuda, MM, Gamboa, D, Ghansah, A, Golassa, L, Goncalves, S, Hamilton, WL, Harrison, GLA, Hart, L, Henrichs, C, Hien, TT, Hill, CA, Hodgson, A, Hubbart, C, Imwong, M, Ishengoma, DS, Jackson, SA, Jacob, CG, Jeffery, B, Jeffreys, AE, Johnson, KJ, Jyothi, D, Kamaliddin, C, Kamau, E, Kekre, M, Kluczynski, K, Kochakarn, T, Konaté, A, Kwiatkowski, DP, Kyaw, MP, Lim, P, Lon, C, Loua, KM, Maïga-Ascofaré, O, Malangone, C, Manske, M, Marfurt, J, Marsh, K, Mayxay, M, Miles, A, Miotto, O, Mobegi, V, Mokuolu, OA, Montgomery, J, Mueller, I, Newton, PN, Nguyen, T, Nguyen, T-N, Noedl, H, Nosten, F, Noviyanti, R, Nzila, A, Ochola-Oyier, LI, Ocholla, H, Oduro, A, Omedo, I, Onyamboko, MA, Ouedraogo, J-B, Oyebola, K, Pearson, RD, Peshu, N, Phyo, AP, Plowe, CV, Price, RN, Pukrittayakamee, S, Randrianarivelojosia, M, Rayner, JC, Ringwald, P, Rockett, KA, Rowlands, K, Ruiz, L, Saunders, D, Shayo, A, Siba, P, Simpson, VJ, Stalker, J, Su, X-Z, Sutherland, C, Takala-Harrison, S, Tavul, L, Thathy, V, Tshefu, A, Verra, F, Vinetz, J, Wellems, TE, Wendler, J, White, NJ, Wright, I, Yavo, W, and Ye, H
- Abstract
MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.
- Published
- 2021
7. Antibodies directed against merozoite surface protein-6 are induced by natural exposure to Plasmodium falciparum in a low transmission environment
- Author
-
JORDAN, S. J., OLIVEIRA, A. L., NEAL, A. T., HERNANDEZ, J. N., BRANCH, O. H., and RAYNER, J. C.
- Published
- 2011
- Full Text
- View/download PDF
8. Population Biology, Evolution, and Immunology of Vaccination and Vaccination Programs
- Author
-
HALLORAN, M. E., ANDERSON, R. M., AZEVEDO-NETO, R. S., BELLINI, W. J., BRANCH, O., BURKE, M. A., COMPANS, R., DAY, K., GOODING, L., GUPTA, S., KATZ, J., KEW, O., KEYSERLING, H., KRAUSE, R., LAL, A. A., MASSAD, E., McLEAN, A. R., ROSA, P., ROTA, P., WIENER, P., WYNN, S. G., and ZANETTA, D. M. T.
- Published
- 1998
9. Genomic epidemiology of artemisinin resistant malaria.
- Author
-
Amato, A., Miotto, O., Woodrow, C.J., Almagro-Garcia, J., Sinha, I., Campino, S., Mead, D., Drury, E., Kekre, M., Sanders, M., Amambua-Ngwa, A., Amaratunga, C., Amenga-Etego, L., Andrianaranjaka, V., Apinjoh, T., Ashley, E., Auburn, S., Awandare, G.A., Baraka, V., Barry, A., Boni, M.F., Borrmann, S., Bousema, T., Branch, O., Bull, P.C., Chotivanich, K., Conway, D.J., Craig, A., Day, N.P., Djimdé, A., Dolecek, C., Dondorp, A.M., Drakeley, C., Duffy, P., et al., Amato, A., Miotto, O., Woodrow, C.J., Almagro-Garcia, J., Sinha, I., Campino, S., Mead, D., Drury, E., Kekre, M., Sanders, M., Amambua-Ngwa, A., Amaratunga, C., Amenga-Etego, L., Andrianaranjaka, V., Apinjoh, T., Ashley, E., Auburn, S., Awandare, G.A., Baraka, V., Barry, A., Boni, M.F., Borrmann, S., Bousema, T., Branch, O., Bull, P.C., Chotivanich, K., Conway, D.J., Craig, A., Day, N.P., Djimdé, A., Dolecek, C., Dondorp, A.M., Drakeley, C., Duffy, P., and et al.
- Abstract
Contains fulltext : 172626.pdf (publisher's version ) (Open Access)
- Published
- 2016
10. Genomic epidemiology of artemisinin resistant malaria
- Author
-
Amato, R., Miotto, O., Woodrow, C.J., Almagro-Garcia, J., Sinha, I., Campino, S., Mead, D., Drury, E., Kekre, M., Sanders, M., Amambua-Ngwa, A., Amaratunga, C., Amenga-Etego, L., Andrianaranjaka, V., Apinjoh, T., Ashley, E., Auburn, S., Awandare, G.A., Baraka, V., Barry, Alyssa, Boni, M.F., Borrmann, S., Bousema, T., Branch, O., Bull, P.C., Chotivanich, K., Conway, D.J., Craig, A., Day, N.P., Djimdé, A., Dolecek, C., Dondorp, A.M., Drakeley, C., Duffy, P., Echeverry, D.F., Egwang, T.G., Fairhurst, R.M., Faiz, A., Fanello, C.I., Hien, T.T., Hodgson, A., Imwong, M., Ishengoma, D., Lim, P., Lon, C., Marfurt, J., Marsh, K., Mayxay, M., Michon, P., Mobegi, V., Mokuolu, O.A., Montgomery, J., Mueller, I., Kyaw, M.P., Newton, P.N., Nosten, F., Noviyanti, R., Nzila, A., Ocholla, H., Oduro, A., Onyamboko, M., Ouedraogo, J.B., Phyo, A.P.P., Plowe, C., Price, R.N., Pukrittayakamee, S., Randrianarivelojosia, M., Ringwald, P., Ruiz, L., Saunders, D., Shayo, A., Siba, P., Takala-Harrison, S., Thanh, T.N.N., Thathy, V., Verra, F., Wendler, J., White, N.J., Ye, H., Cornelius, V.J., Giacomantonio, R., Muddyman, D., Henrichs, C., Malangone, C., Jyothi, D., Pearson, R.D., Rayner, J.C., McVean, G., Rockett, K.A., Miles, A., Vauterin, P., Jeffery, B., Manske, M., Stalker, J., Macinnis, B., Kwiatkowski, D.P., Amato, R., Miotto, O., Woodrow, C.J., Almagro-Garcia, J., Sinha, I., Campino, S., Mead, D., Drury, E., Kekre, M., Sanders, M., Amambua-Ngwa, A., Amaratunga, C., Amenga-Etego, L., Andrianaranjaka, V., Apinjoh, T., Ashley, E., Auburn, S., Awandare, G.A., Baraka, V., Barry, Alyssa, Boni, M.F., Borrmann, S., Bousema, T., Branch, O., Bull, P.C., Chotivanich, K., Conway, D.J., Craig, A., Day, N.P., Djimdé, A., Dolecek, C., Dondorp, A.M., Drakeley, C., Duffy, P., Echeverry, D.F., Egwang, T.G., Fairhurst, R.M., Faiz, A., Fanello, C.I., Hien, T.T., Hodgson, A., Imwong, M., Ishengoma, D., Lim, P., Lon, C., Marfurt, J., Marsh, K., Mayxay, M., Michon, P., Mobegi, V., Mokuolu, O.A., Montgomery, J., Mueller, I., Kyaw, M.P., Newton, P.N., Nosten, F., Noviyanti, R., Nzila, A., Ocholla, H., Oduro, A., Onyamboko, M., Ouedraogo, J.B., Phyo, A.P.P., Plowe, C., Price, R.N., Pukrittayakamee, S., Randrianarivelojosia, M., Ringwald, P., Ruiz, L., Saunders, D., Shayo, A., Siba, P., Takala-Harrison, S., Thanh, T.N.N., Thathy, V., Verra, F., Wendler, J., White, N.J., Ye, H., Cornelius, V.J., Giacomantonio, R., Muddyman, D., Henrichs, C., Malangone, C., Jyothi, D., Pearson, R.D., Rayner, J.C., McVean, G., Rockett, K.A., Miles, A., Vauterin, P., Jeffery, B., Manske, M., Stalker, J., Macinnis, B., and Kwiatkowski, D.P.
- Published
- 2016
11. Genomic epidemiology of artemisinin resistant malaria
- Author
-
Amato, R, Miotto, O, Woodrow, CJ, Almagro-Garcia, J, Sinha, I, Campino, S, Mead, D, Drury, E, Kekre, M, Sanders, M, Amambua-Ngwa, A, Amaratunga, C, Amenga-Etego, L, Andrianaranjaka, V, Apinjoh, T, Ashley, E, Auburn, S, Awandare, GA, Baraka, V, Barry, A, Boni, MF, Borrmann, S, Bousema, T, Branch, O, Bull, PC, Chotivanich, K, Conway, DJ, Craig, A, Day, NP, Djimde, A, Dolecek, C, Dondorp, AM, Drakeley, C, Duffy, P, Echeverry, DF, Egwang, TG, Fairhurst, RM, Faiz, MA, Fanello, CI, Tran, TH, Hodgson, A, Imwong, M, Ishengoma, D, Lim, P, Lon, C, Marfurt, J, Marsh, K, Mayxay, M, Michon, P, Mobegi, V, Mokuolu, OA, Montgomery, J, Mueller, I, Kyaw, MP, Newton, PN, Nosten, F, Noviyanti, R, Nzila, A, Ocholla, H, Oduro, A, Onyamboko, M, Ouedraogo, J-B, Phyo, APP, Plowe, C, Price, RN, Pukrittayakamee, S, Randrianarivelojosia, M, Ringwald, P, Ruiz, L, Saunders, D, Shayo, A, Siba, P, Takala-Harrison, S, Thanh, T-NN, Thathy, V, Verra, F, Wendler, J, White, NJ, Ye, H, Cornelius, VJ, Giacomantonio, R, Muddyman, D, Henrichs, C, Malangone, C, Jyothi, D, Pearson, RD, Rayner, JC, McVean, G, Rockett, KA, Miles, A, Vauterin, P, Jeffery, B, Manske, M, Stalker, J, Maclnnis, B, Kwiatkowski, DP, Amato, R, Miotto, O, Woodrow, CJ, Almagro-Garcia, J, Sinha, I, Campino, S, Mead, D, Drury, E, Kekre, M, Sanders, M, Amambua-Ngwa, A, Amaratunga, C, Amenga-Etego, L, Andrianaranjaka, V, Apinjoh, T, Ashley, E, Auburn, S, Awandare, GA, Baraka, V, Barry, A, Boni, MF, Borrmann, S, Bousema, T, Branch, O, Bull, PC, Chotivanich, K, Conway, DJ, Craig, A, Day, NP, Djimde, A, Dolecek, C, Dondorp, AM, Drakeley, C, Duffy, P, Echeverry, DF, Egwang, TG, Fairhurst, RM, Faiz, MA, Fanello, CI, Tran, TH, Hodgson, A, Imwong, M, Ishengoma, D, Lim, P, Lon, C, Marfurt, J, Marsh, K, Mayxay, M, Michon, P, Mobegi, V, Mokuolu, OA, Montgomery, J, Mueller, I, Kyaw, MP, Newton, PN, Nosten, F, Noviyanti, R, Nzila, A, Ocholla, H, Oduro, A, Onyamboko, M, Ouedraogo, J-B, Phyo, APP, Plowe, C, Price, RN, Pukrittayakamee, S, Randrianarivelojosia, M, Ringwald, P, Ruiz, L, Saunders, D, Shayo, A, Siba, P, Takala-Harrison, S, Thanh, T-NN, Thathy, V, Verra, F, Wendler, J, White, NJ, Ye, H, Cornelius, VJ, Giacomantonio, R, Muddyman, D, Henrichs, C, Malangone, C, Jyothi, D, Pearson, RD, Rayner, JC, McVean, G, Rockett, KA, Miles, A, Vauterin, P, Jeffery, B, Manske, M, Stalker, J, Maclnnis, B, and Kwiatkowski, DP
- Abstract
The current epidemic of artemisinin resistant Plasmodium falciparum in Southeast Asia is the result of a soft selective sweep involving at least 20 independent kelch13 mutations. In a large global survey, we find that kelch13 mutations which cause resistance in Southeast Asia are present at low frequency in Africa. We show that African kelch13 mutations have originated locally, and that kelch13 shows a normal variation pattern relative to other genes in Africa, whereas in Southeast Asia there is a great excess of non-synonymous mutations, many of which cause radical amino-acid changes. Thus, kelch13 is not currently undergoing strong selection in Africa, despite a deep reservoir of variations that could potentially allow resistance to emerge rapidly. The practical implications are that public health surveillance for artemisinin resistance should not rely on kelch13 data alone, and interventions to prevent resistance must account for local evolutionary conditions, shown by genomic epidemiology to differ greatly between geographical regions.
- Published
- 2016
12. The impact of standard and hard-coded parameters on the hydrologic fluxes in the Noah-MP land surface model
- Author
-
Cuntz, Matthias, Mai, Juliane, Samaniego, Luis, Clark, M., Wulfmeyer, V., Branch, O., Attinger, Sabine, Thober, Stephan, Cuntz, Matthias, Mai, Juliane, Samaniego, Luis, Clark, M., Wulfmeyer, V., Branch, O., Attinger, Sabine, and Thober, Stephan
- Abstract
Land surface models incorporate a large number of process descriptions, containing a multitude of parameters. These parameters are typically read from tabulated input files. Some of these parameters might be fixed numbers in the computer code though, which hinders model agility during calibration. Here we identified 139 hard-coded parameters in the model code of the Noah land surface model with multiple process options (Noah-MP). We performed a Sobol' global sensitivity analysis of Noah-MP for a specific set of process options which includes 42 out of the 71 standard parameters and 75 of the 139 hard-coded parameters. The sensitivities of the hydrologic output fluxes latent heat and total runoff as well as their component fluxes were evaluated at twelve catchments within the United States with very different hydro-meteorological regimes.Noah-MP's hydrologic output fluxes are sensitive to two thirds of its applicable standard parameters (i.e. Sobol' indexes above 1%). The most sensitive parameter is, however, a hard-coded value in the formulation of soil surface resistance for direct evaporation, which proved to be oversensitive in other land surface models as well. Surface runoff is sensitive to almost all hard-coded parameters of the snow processes and the meteorological inputs. These parameter sensitivities diminish in total runoff. Assessing these parameters in model calibration would require detailed snow observations or the calculation of hydrologic signatures of the runoff data. Latent heat and total runoff exhibit very similar sensitivities because of their tight coupling via the water balance. A calibration of Noah-MP against either of these fluxes should therefore give comparable results. Moreover, these fluxes are sensitive to both plant and soil parameters. Calibrating, for example, only soil parameters thus limits the ability to derive realistic model parameters.It is thus recommended to include the most sensitive hard-coded model parameters that were ex
- Published
- 2016
13. Simulation of semi-arid biomass plantations and irrigation using the WRF-NOAH model – a comparison with observations from Israel
- Author
-
Branch, O., primary, Warrach-Sagi, K., additional, Wulfmeyer, V., additional, and Cohen, S., additional
- Published
- 2014
- Full Text
- View/download PDF
14. Irrigated plantations and their effect on energy fluxes in a semi-arid region of Israel – a validated 3-D model simulation
- Author
-
Branch, O., primary, Warrach-Sagi, K., additional, Wulfmeyer, V., additional, and Cohen, S., additional
- Published
- 2013
- Full Text
- View/download PDF
15. Genetic diversity in merozoite surface protein-1 and 2 amongPlasmodium falciparumisolates from malarious districts of tribal dominant state of Jharkhand, India
- Author
-
Hussain, M M, primary, Sohail, M, additional, Kumar, R, additional, Branch, O H, additional, Adak, T, additional, and Raziuddin, M, additional
- Published
- 2011
- Full Text
- View/download PDF
16. Plasmodium falciparum Genetic Diversity Maintained and Amplified Over 5 Years of a Low Transmission Endemic in the Peruvian Amazon
- Author
-
Branch, O. H., primary, Sutton, P. L., additional, Barnes, C., additional, Castro, J. C., additional, Hussin, J., additional, Awadalla, P., additional, and Hijar, G., additional
- Published
- 2010
- Full Text
- View/download PDF
17. Antibody responses to repetitive epitopes of the circumsporozoite protein, liver stage antigen-1, and merozoite surface protein-2 in infants residing in a Plasmodium falciparum-hyperendemic area of western Kenya. XIII. Asembo Bay Cohort Project.
- Author
-
Zhou, Z, primary, Nahlen, B L, additional, Lal, A A, additional, Branch, O H, additional, Xiao, L, additional, and Kariuki, S, additional
- Published
- 2002
- Full Text
- View/download PDF
18. Irrigated plantations and their effect on energy fluxes in a semi-arid region of Israel -- a validated 3-D model simulation.
- Author
-
Branch, O., Warrach-Sagi, K., Wulfmeyer, V., and Cohen, f. S.
- Abstract
A large irrigated biomass plantation was simulated in an arid region of Israel within the WRF-NOAH coupled atmospheric/land surface model in order to assess land surface atmosphere feedbacks. Simulations were carried out for the 2012 summer season (JJA). The irrigated plantations were simulated by prescribing tailored land surface and soil/plant parameters, and by implementing a newly devised, controllable subsurface irrigation scheme within NOAH. Two model cases studies were considered and compared -- Impact and Control. Impact simulates a hypothetical 10 km x10 km irrigated plantation. Control represents a baseline and uses the existing land surface data, where the predominant land surface type in the area is bare desert soil. Central to the study is model validation against observations collected for the study over the same period. Surface meteorological and soil observations were made at a desert site and from a 400 ha Simmondsia chinensis (Jojoba) plantation. Control was validated with data from the desert, and Impact from the Jojoba. Finally, estimations were made of the energy balance, applying two Penman--Monteith based methods along with observed meteorological data. These estimations were compared with simulated energy fluxes. Control simulates the daytime desert surface 2m air temperatures (T2) with less than 0.2 °C deviation and the vapour pressure deficit (VPD) to within 0.25 hPa. Desert wind speed (U) is simulated to within 0.5ms and the net surface radiation (R
n ) to 25Wm-2 . Soil heat flux (G) is not so accurately simulated by Control (up to 30Wm-2 deviation) and 5 cm soil temperatures (ST5) are simulated to within 1.5 °C. Impact simulates daytime T2 over irrigated vegetation to within 1-1.5 °C, the VPD to 0.5 hPa, Rn to 50Wm-2 . and ST5 to within 2 °C. Simulated Impact G deviates up to 40Wm-2 , highlighting a need for re-parameterisation or better soil classification, but the overall contribution to the energy balance is small (5-6%). During the night, significant T2 and ST5 cold biases of 2-4 C are present. Diurnal latent heat values from WRF Impact correspond closely with Penman--Monteith estimation curves, and latent heat magnitudes of 160Wm over the plantation are usual. Simulated plantation sensible heat fluxes are high (450Wm-2 ) -- around 100-110Wm-2 higher than over the surrounding desert. The high relative HFX over the vegetation, driven by high Rn and high surface resistances, indicate that low Bowen ratios should not necessarily be assumed when irrigated plantations are implemented in, and optimized for arid regions. Furthermore, the high plantation T2 magnitudes highlight the importance of considering diurnal dynamics, which drive the evolution of boundary layers, rather than only on daily mean statistics which often indicate an irrigation cooling effect. [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
19. A longitudinal investigation of IgG and IgM antibody responses to the merozoite surface protein-1 19-kiloDalton domain of Plasmodium falciparum in pregnant women and infants: associations with febrile illness, parasitemia, and anemia.
- Author
-
Branch, O H, primary, Oloo, A J, additional, Lal, A A, additional, Bloland, P B, additional, Hawley, W A, additional, Udhayakumar, V, additional, Hightower, A W, additional, Kaslow, D C, additional, and Nahlen, B L, additional
- Published
- 1998
- Full Text
- View/download PDF
20. Identification of T and B cell epitopes recognized by humans in the C-terminal 42-kDa domain of the Plasmodium falciparum merozoite surface protein (MSP)-1.
- Author
-
Udhayakumar, V, primary, Anyona, D, additional, Kariuki, S, additional, Shi, Y P, additional, Bloland, P B, additional, Branch, O H, additional, Weiss, W, additional, Nahlen, B L, additional, Kaslow, D C, additional, and Lal, A A, additional
- Published
- 1995
- Full Text
- View/download PDF
21. Plasmodium falciparum genotypes, low complexity of infection, and resistance to subsequent malaria in participants in the Asembo Bay Cohort Project.
- Author
-
Branch, O H, Takala, S, Kariuki, S, Nahlen, B L, Kolczak, M, Hawley, W, and Lal, A A
- Abstract
To assess the relationship between the within-host diversity of malaria infections and the susceptibility of the host to subsequent infection, we genotyped 60 children's successive infections from birth through 3 years of life. MSP-1 Block2 genotypes were used to estimate the complexity of infection (COI). Malaria transmission and age were positively associated with the number of K1 and Mad20 alleles detected (COI(KM)) (P < 0.003). Controlling for previous parasitemia, transmission, drug treatment, parasite density, sickle cell, and age, COI(KM) was negatively correlated with resistance to parasitemia of > 500/microl (P < 0.0001). Parasitemias with the RO-genotype were more resistant than those without this genotype (P < 0.0000). The resistance in low COI(KM) infections was not genotype specific. We discuss the impact of genotype-transcending immunity to conserved antigenic determinants. We also propose a diversity-driven immunomodulation hypothesis that may explain the delayed development of natural immunity in the first few years of life and suggest that interventions that decrease the COI(KM) could facilitate the development of protective immunity.
- Published
- 2001
22. Genetic diversity of the malaria vaccine candidate plasmodium falciparum merozoite surface protein-3 in a hypoendemic transmission environment
- Author
-
Stephen Jordan, Branch, O. H., Castro, J. C., Oster, R. A., and Rayner, J. C.
23. Sexual recombination is a signature of a persisting malaria epidemic in Peru
- Author
-
Sutton Patrick L, Torres Lindsay P, and Branch OraLee H
- Subjects
Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background The aim of this study was to consider the impact that multi-clone, complex infections have on a parasite population structure in a low transmission setting. In general, complexity of infection (minimum number of clones within an infection) and the overall population level diversity is expected to be minimal in low transmission settings. Additionally, the parasite population structure is predicted to be clonal, rather than sexual due to infrequent parasite inoculation and lack of recombination between genetically distinct clones. However, in this low transmission of the Peruvian Amazon, complex infections are becoming more frequent, in spite of decreasing infection prevalence. In this study, it was hypothesized that sexual recombination between distinct clonal lineages of Plasmodium falciparum parasites were altering the subpopulation structure and effectively maintaining the population-level diversity. Methods Fourteen microsatellite markers were chosen to describe the genetic diversity in 313 naturally occurring P. falciparum infections from Peruvian Amazon. The population and subpopulation structure was characterized by measuring: clusteredness, expected heterozygosity (He), allelic richness, private allelic richness, and linkage disequilibrium. Next, microsatellite haplotypes and alleles were correlated with P. falciparum merozoite surface protein 1 Block 2 (Pfmsp1-B2) to examine the presence of recombinant microsatellite haplotypes. Results The parasite population structure consists of six genetically diverse subpopulations of clones, called "clusters". Clusters 1, 3, 4, and 6 have unique haplotypes that exceed 70% of the total number of clones within each cluster, while Clusters 2 and 5 have a lower proportion of unique haplotypes, but still exceed 46%. By measuring the He, allelic richness, and private allelic richness within each of the six subpopulations, relatively low levels of genetic diversity within each subpopulation (except Cluster 4) are observed. This indicated that the number of alleles, and not the combination of alleles, are limited. Next, the standard index of association (IAS) was measured, which revealed a significant decay in linkage disequilibrium (LD) associated with Cluster 6, which is indicative of independent assortment of alleles. This decay in LD is a signature of this subpopulation approaching linkage equilibrium by undergoing sexual recombination. To trace possible recombination events, the two most frequent microsatellite haplotypes observed over time (defined by either a K1 or Mad20) were selected as the progenitors and then potential recombinants were identified in within the natural population. Conclusions Contrary to conventional low transmission models, this study provides evidence of a parasite population structure that is superficially defined by a clonal backbone. Sexual recombination does occur and even arguably is responsible for maintaining the substructure of this population.
- Published
- 2011
- Full Text
- View/download PDF
24. Limited variation in vaccine candidate Plasmodium falciparum Merozoite Surface Protein-6 over multiple transmission seasons
- Author
-
Branch OraLee H, Hernandez Jean N, Oliveira Ana L, Jordan Stephen J, Neal Aaron T, and Rayner Julian C
- Subjects
Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Plasmodium falciparum Merozoite Surface Protein-6 (PfMSP6) is a component of the complex proteinacious coat that surrounds P. falciparum merozoites. This location, and the presence of anti-PfMSP6 antibodies in P. falciparum-exposed individuals, makes PfMSP6 a potential blood stage vaccine target. However, genetic diversity has proven to be a major hurdle for vaccines targeting other blood stage P. falciparum antigens, and few endemic field studies assessing PfMSP6 gene diversity have been conducted. This study follows PfMSP6 diversity in the Peruvian Amazon from 2003 to 2006 and is the first longitudinal assessment of PfMSP6 sequence dynamics. Methods Parasite DNA was extracted from 506 distinct P. falciparum infections spanning the transmission seasons from 2003 to 2006 as part of the Malaria Immunology and Genetics in the Amazon (MIGIA) cohort study near Iquitos, Peru. PfMSP6 was amplified from each sample using a nested PCR protocol, genotyped for allele class by agarose gel electrophoresis, and sequenced to detect diversity. Allele frequencies were analysed using JMP v.8.0.1.0 and correlated with clinical and epidemiological data collected as part of the MIGIA project. Results Both PfMSP6 allele classes, K1-like and 3D7-like, were detected at the study site, confirming that both are globally distributed. Allele frequencies varied significantly between transmission seasons, with 3D7-class alleles dominating and K1-class alleles nearly disappearing in 2005 and 2006. There was a significant association between allele class and village location (p-value = 0.0008), but no statistically significant association between allele class and age, sex, or symptom status. No intra-allele class sequence diversity was detected. Conclusions Both PfMSP6 allele classes are globally distributed, and this study shows that allele frequencies can fluctuate significantly between communities separated by only a few kilometres, and over time in the same community. By contrast, PfMSP6 was highly stable at the sequence level, with no SNPs detected in the 506 samples analysed. This limited diversity supports further investigation of PfMSP6 as a blood stage vaccine candidate, with the clear caveat that any such vaccine must either contain both alleles or generate cross-protective responses that react against both allele classes. Detailed immunoepidemiology studies are needed to establish the viability of these approaches before PfMSP6 advances further down the vaccine development pipeline.
- Published
- 2010
- Full Text
- View/download PDF
25. The Plasmodium falciparum merozoite surface protein-1 19 KD antibody response in the Peruvian Amazon predominantly targets the non-allele specific, shared sites of this antigen
- Author
-
Silva Claudia, Clark Eva H, Sutton Patrick L, and Branch OraLee H
- Subjects
Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Plasmodium falciparum re-emerged in Iquitos, Peru in 1994 and is now hypoendemic (< 0.5 infections/person/year). Purportedly non-immune individuals with discrete (non-overlapping) P. falciparum infections can be followed using this population dynamic. Previous work demonstrated a strong association between this population's antibody response to PfMSP1-19KD and protection against febrile illness and parasitaemia. Therefore, some selection for PfMSP1-19KD allelic diversity would be expected if the protection is to allele-specific sites of PfMSP1-19KD. Here, the potential for allele-specific polymorphisms in this population is investigated, and the allele-specificity of antibody responses to PfMSP1-19KD are determined. Methods The 42KD region in PfMSP1 was genotyped from 160 individual infections collected between 2003 and 2007. Additionally, the polymorphic block 2 region of Pfmsp1 (Pfmsp1-B2) was genotyped in 781 infection-months to provide a baseline for population-level diversity. To test whether PfMSP1-19KD genetic diversity had any impact on antibody responses, ELISAs testing IgG antibody response were performed on individuals using all four allele-types of PfMSP1-19KD. An antibody depletion ELISA was used to test the ability of antibodies to cross-react between allele-types. Results Despite increased diversity in Pfmsp1-B2, limited diversity within Pfmsp1-42KD was observed. All 160 infections genotyped were Mad20-like at the Pfmsp1-33KD locus. In the Pfmsp1-19KD locus, 159 (99.4%) were the Q-KSNG-F haplotype and 1 (0.6%) was the E-KSNG-L haplotype. Antibody responses in 105 individuals showed that Q-KNG and Q-TSR alleles generated the strongest immune responses, while Q-KNG and E-KNG responses were more concordant with each other than with those from Q-TSR and E-TSR, and vice versa. The immuno-depletion ELISAs showed all samples responded to the antigenic sites shared amongst all allelic forms of PfMSP1-19KD. Conclusions A non-allele specific antibody response in PfMSP1-19KD may explain why other allelic forms have not been maintained or evolved in this population. This has important implications for the use of PfMSP1-19KD as a vaccine candidate. It is possible that Peruvians have increased antibody responses to the shared sites of PfMSP1-19KD, either due to exposure/parasite characteristics or due to a human-genetic predisposition. Alternatively, these allelic polymorphisms are not immune-specific even in other geographic regions, implying these polymorphisms may be less important in immune evasion that previous studies suggest.
- Published
- 2010
- Full Text
- View/download PDF
26. Antibody response dynamics to the Plasmodium falciparum conserved vaccine candidate antigen, merozoite surface protein-1 C-terminal 19kD (MSP1-19kD), in Peruvians exposed to hypoendemic malaria transmission
- Author
-
Gamboa Dionicia, Soto-Cornejo Katherine E, Hernandez Jean N, Clark Eva H, Torres Katherine J, and Branch OraLee H
- Subjects
Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background In high-transmission areas, developing immunity to symptomatic Plasmodium falciparum infections requires 2–10 years of uninterrupted exposure. Delayed malaria-immunity has been attributed to difficult-to-develop and then short-lived antibody responses. Methods In a study area with P. falciparum infections/person/year, antibody responses to the MSP1-19kD antigen were evaluated and associations with P. falciparum infections in children and adults. In months surrounding and during the malaria seasons of 2003–2004, 1,772 participants received ≥6 active visits in one study-year. Community-wide surveys were conducted at the beginning and end of each malaria season, and weekly active visits were completed for randomly-selected individuals each month. There were 79 P. falciparum infections with serum samples collected during and approximately one month before and after infection. Anti-MSP1-19kD IgG levels were measured by ELISA. Results The infection prevalence during February-July was similar in children (0.02–0.12 infections/person/month) and adults (0.03–0.14 infections/person/month) and was negligible in the four-month dry season. In children and adults, the seroprevalence was maintained in the beginning (children = 28.9%, adults = 61.8%) versus ending malaria-season community survey (children = 26.7%, adults = 64.6%). Despite the four-month non-transmission season, the IgG levels in Plasmodium-negative adults were similar to P. falciparum-positive adults. Although children frequently responded upon infection, the transition from a negative/low level before infection to a high level during/after infection was slower in children. Adults and children IgG-positive before infection had reduced symptoms and parasite density. Conclusion Individuals in low transmission areas can rapidly develop and maintain αMSP1-19kD IgG responses for >4 months, unlike responses reported in high transmission study areas. A greater immune capacity might contribute to the frequent asymptomatic P. falciparum infections in this Peruvian population.
- Published
- 2008
- Full Text
- View/download PDF
27. Genetic diversity of vaccine candidate antigens in Plasmodium falciparum isolates from the Amazon basin of Peru
- Author
-
Lucas Carmen M, Escalante Ananias A, Branch OraLee H, Chenet Stella M, and Bacon David J
- Subjects
Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Several of the intended Plasmodium falciparum vaccine candidate antigens are highly polymorphic and could render a vaccine ineffective if their antigenic sites were not represented in the vaccine. In this study, characterization of genetic variability was performed in major B and T-cell epitopes within vaccine candidate antigens in isolates of P. falciparum from Peru. Methods DNA sequencing analysis was completed on 139 isolates of P. falciparum collected from endemic areas of the Amazon basin in Loreto, Peru from years 1998 to 2006. Genetic diversity was determined in immunological important regions in circumsporozoite protein (CSP), merozoite surface protein-1 (MSP-1), apical membrane antigen-1 (AMA-1), liver stage antigen-1 (LSA-1) and thrombospondin-related anonymous protein (TRAP). Alleles identified by DNA sequencing were aligned with the vaccine strain 3D7 and DNA polymorphism analysis and FST study-year pairwise comparisons were done using the DnaSP software. Multilocus analysis (MLA) was performed and average of expected heterozygosity was calculated for each loci and haplotype over time. Results Three different alleles for CSP, seven for MSP-1 Block 2, one for MSP-1 Block 17, three for AMA-1 and for LSA-1 each and one for TRAP were identified. There were 24 different haplotypes in 125 infections with complete locus typing for each gene. Conclusion Characterization of the genetic diversity in Plasmodium isolates from the Amazon Region of Peru showed that P. falciparum T and B cell epitopes in these antigens have polymorphisms more similar to India than to Africa. These findings are helpful in the formulation of a vaccine considering restricted repertoire populations.
- Published
- 2008
- Full Text
- View/download PDF
28. Clustered local transmission and asymptomatic Plasmodium falciparum and Plasmodium vivax malaria infections in a recently emerged, hypoendemic Peruvian Amazon community
- Author
-
Alvarez Eugenia, Roncal Norma, Alava Freddy F, Hernandez Jean N, Gamboa Dionicia V, Casapia W Martin, Branch OraLee, Perez Enrique J, and Gotuzzo Eduardo
- Subjects
Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background There is a low incidence of malaria in Iquitos, Peru, suburbs detected by passive case-detection. This low incidence might be attributable to infections clustered in some households/regions and/or undetected asymptomatic infections. Methods Passive case-detection (PCD) during the malaria season (February-July) and an active case-detection (ACD) community-wide survey (March) surveyed 1,907 persons. Each month, April-July, 100-metre at-risk zones were defined by location of Plasmodium falciparum infections in the previous month. Longitudinal ACD and PCD (ACP+PCD) occurred within at-risk zones, where 137 houses (573 persons) were randomly selected as sentinels, each with one month of weekly active sampling. Entomological captures were conducted in the sentinel houses. Results The PCD incidence was 0.03 P. falciparum and 0.22 Plasmodium vivax infections/person/malaria-season. However, the ACD+PCD prevalence was 0.13 and 0.39, respectively. One explanation for this 4.33 and 1.77-fold increase, respectively, was infection clustering within at-risk zones and contiguous households. Clustering makes PCD, generalized to the entire population, artificially low. Another attributable-factor was that only 41% and 24% of the P. falciparum and P. vivax infections were associated with fever and 80% of the asymptomatic infections had low-density or absent parasitaemias the following week. After accounting for asymptomatic infections, a 2.6-fold increase in ACD+PCD versus PCD was attributable to clustered transmission in at-risk zones. Conclusion Even in low transmission, there are frequent highly-clustered asymptomatic infections, making PCD an inadequate measure of incidence. These findings support a strategy of concentrating ACD and insecticide campaigns in houses adjacent to houses were malaria was detected one month prior.
- Published
- 2005
- Full Text
- View/download PDF
29. A Tale.
- Author
-
Branch, O.
- Published
- 1839
30. ORWELL, Vt. March 30th, 1872.
- Author
-
BRANCH, O. S.
- Published
- 1872
31. Predominant Economies 11.
- Author
-
United States Army Service Forces, Branch of Research and Analysis, OSS, and A. Hoen & Co., Inc.
- Subjects
Commerce - Abstract
Full color. Preface states, "Most of the maps in this atlas are original." International boundaries on the maps generally are as of 1937. Sinusoidal equal-area projection generally used.
- Published
- 1943
32. Major Agricultural Regions 12.
- Author
-
United States Army Service Forces, Branch of Research and Analysis, OSS, and A. Hoen & Co., Inc.
- Subjects
Agriculture - Abstract
Full color. Preface states, "Most of the maps in this atlas are original." International boundaries on the maps generally are as of 1937. Sinusoidal equal-area projection generally used.
- Published
- 1943
33. Languages 9.
- Author
-
United States Army Service Forces, Branch of Research and Analysis, OSS, and A. Hoen & Co., Inc.
- Subjects
Languages - Abstract
Full color. Preface states, "Most of the maps in this atlas are original." International boundaries on the maps generally are as of 1937. Sinusoidal equal-area projection generally used.
- Published
- 1943
34. Soils 6.
- Author
-
United States Army Service Forces, Branch of Research and Analysis, OSS, and A. Hoen & Co., Inc.
- Subjects
Soils - Abstract
Full color. Preface states, "Most of the maps in this atlas are original." International boundaries on the maps generally are as of 1937. Sinusoidal equal-area projection generally used.
- Published
- 1943
35. Climate 4.
- Author
-
United States Army Service Forces, Branch of Research and Analysis, OSS, and A. Hoen & Co., Inc.
- Subjects
Climate - Abstract
Full color. Preface states, "Most of the maps in this atlas are original." International boundaries on the maps generally are as of 1937. Sinusoidal equal-area projection generally used.
- Published
- 1943
36. Natural Vegetation 5.
- Author
-
United States Army Service Forces, Branch of Research and Analysis, OSS, and A. Hoen & Co., Inc.
- Subjects
Vegetation - Abstract
Full color. Preface states, "Most of the maps in this atlas are original." International boundaries on the maps generally are as of 1937. Sinusoidal equal-area projection generally used.
- Published
- 1943
37. Pf7: an open dataset of Plasmodium falciparum genome variation in 20,000 worldwide samples.
- Author
-
Abdel Hamid MM, Abdelraheem MH, Acheampong DO, Ahouidi A, Ali M, Almagro-Garcia J, Amambua-Ngwa A, Amaratunga C, Amenga-Etego L, Andagalu B, Anderson T, Andrianaranjaka V, Aniebo I, Aninagyei E, Ansah F, Ansah PO, Apinjoh T, Arnaldo P, Ashley E, Auburn S, Awandare GA, Ba H, Baraka V, Barry A, Bejon P, Bertin GI, Boni MF, Borrmann S, Bousema T, Bouyou-Akotet M, Branch O, Bull PC, Cheah H, Chindavongsa K, Chookajorn T, Chotivanich K, Claessens A, Conway DJ, Corredor V, Courtier E, Craig A, D'Alessandro U, Dama S, Day N, Denis B, Dhorda M, Diakite M, Djimde A, Dolecek C, Dondorp A, Doumbia S, Drakeley C, Drury E, Duffy P, Echeverry DF, Egwang TG, Enosse SMM, Erko B, Fairhurst RM, Faiz A, Fanello CA, Fleharty M, Forbes M, Fukuda M, Gamboa D, Ghansah A, Golassa L, Goncalves S, Harrison GLA, Healy SA, Hendry JA, Hernandez-Koutoucheva A, Hien TT, Hill CA, Hombhanje F, Hott A, Htut Y, Hussein M, Imwong M, Ishengoma D, Jackson SA, Jacob CG, Jeans J, Johnson KJ, Kamaliddin C, Kamau E, Keatley J, Kochakarn T, Konate DS, Konaté A, Kone A, Kwiatkowski DP, Kyaw MP, Kyle D, Lawniczak M, Lee SK, Lemnge M, Lim P, Lon C, Loua KM, Mandara CI, Marfurt J, Marsh K, Maude RJ, Mayxay M, Maïga-Ascofaré O, Miotto O, Mita T, Mobegi V, Mohamed AO, Mokuolu OA, Montgomery J, Morang'a CM, Mueller I, Murie K, Newton PN, Ngo Duc T, Nguyen T, Nguyen TN, Nguyen Thi Kim T, Nguyen Van H, Noedl H, Nosten F, Noviyanti R, Ntui VN, Nzila A, Ochola-Oyier LI, Ocholla H, Oduro A, Omedo I, Onyamboko MA, Ouedraogo JB, Oyebola K, Oyibo WA, Pearson R, Peshu N, Phyo AP, Plowe CV, Price RN, Pukrittayakamee S, Quang HH, Randrianarivelojosia M, Rayner JC, Ringwald P, Rosanas-Urgell A, Rovira-Vallbona E, Ruano-Rubio V, Ruiz L, Saunders D, Shayo A, Siba P, Simpson VJ, Sissoko MS, Smith C, Su XZ, Sutherland C, Takala-Harrison S, Talman A, Tavul L, Thanh NV, Thathy V, Thu AM, Toure M, Tshefu A, Verra F, Vinetz J, Wellems TE, Wendler J, White NJ, Whitton G, Yavo W, and van der Pluijm RW
- Abstract
We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network. It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented. For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations. We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent. We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines. Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website., Competing Interests: No competing interests were disclosed., (Copyright: © 2023 MalariaGEN et al.)
- Published
- 2023
- Full Text
- View/download PDF
38. Reply to Wang and D'Odorico: On the sustainability of large-scale desert plantations as a partial solution for climate change.
- Author
-
Branch O and Wulfmeyer V
- Subjects
- Desert Climate, Climate Change, Conservation of Natural Resources
- Abstract
Competing Interests: The authors declare no competing interest.
- Published
- 2019
- Full Text
- View/download PDF
39. Deliberate enhancement of rainfall using desert plantations.
- Author
-
Branch O and Wulfmeyer V
- Subjects
- Atmosphere chemistry, Carbon Sequestration, Climate Change, Ecosystem, Models, Theoretical, Soil chemistry, Trees physiology, Desert Climate, Forestry, Rain
- Abstract
Large-scale afforestation is increasingly being considered as a negative emissions method for sequestering large quantities of atmospheric CO
2 At the same time, regional weather modification methods, like cloud seeding, are being used to counteract increasing water scarcity in arid regions. Large-scale sustainable desert agroforestry plantations can contribute to climate change mitigation and can also be used to modify regional climate, particularly rainfall. Climate impacts from plantations need to be well understood before considering implementation. Typically, impact studies are attempted at continental or global scales and use coarse-resolution models, which suffer from severe systematic errors. This is highly problematic because decision makers should only countenance geoengineering schemes like global afforestation if impacts are understood on the regional scale. We posit the necessity of using high-resolution regional models with sophisticated representations of land-atmosphere feedback and vegetation. This approach allows for studying desert plantations and the process chain leading to climate modification. We demonstrate that large-scale plantations enhance regional clouds and rainfall and derive an index for predicting plantation impacts. Thus, desert plantations represent a unique environmental solution via predictable regional weather modification and carbon storage., Competing Interests: The authors declare no conflict of interest., (Copyright © 2019 the Author(s). Published by PNAS.)- Published
- 2019
- Full Text
- View/download PDF
40. Modelling the potential of focal screening and treatment as elimination strategy for Plasmodium falciparum malaria in the Peruvian Amazon Region.
- Author
-
Rosas-Aguirre A, Erhart A, Llanos-Cuentas A, Branch O, Berkvens D, Abatih E, Lambert P, Frasso G, Rodriguez H, Gamboa D, Sihuincha M, Rosanas-Urgell A, D'Alessandro U, and Speybroeck N
- Subjects
- Cohort Studies, Female, Humans, Malaria, Falciparum drug therapy, Malaria, Falciparum epidemiology, Malaria, Falciparum parasitology, Male, Models, Theoretical, Peru epidemiology, Plasmodium falciparum drug effects, Plasmodium falciparum genetics, Plasmodium falciparum isolation & purification, Plasmodium falciparum physiology, Rural Population, Antimalarials therapeutic use, Malaria, Falciparum prevention & control
- Abstract
Background: Focal screening and treatment (FSAT) of malaria infections has recently been introduced in Peru to overcome the inherent limitations of passive case detection (PCD) and further decrease the malaria burden. Here, we used a relatively straightforward mathematical model to assess the potential of FSAT as elimination strategy for Plasmodium falciparum malaria in the Peruvian Amazon Region., Methods: A baseline model was developed to simulate a scenario with seasonal malaria transmission and the effect of PCD and treatment of symptomatic infections on the P. falciparum malaria transmission in a low endemic area of the Peruvian Amazon. The model was then adjusted to simulate intervention scenarios for predicting the long term additional impact of FSAT on P. falciparum malaria prevalence and incidence. Model parameterization was done using data from a cohort study in a rural Amazonian community as well as published transmission parameters from previous studies in similar areas. The effect of FSAT timing and frequency, using either microscopy or a supposed field PCR, was assessed on both predicted incidence and prevalence rates., Results: The intervention model indicated that the addition of FSAT to PCD significantly reduced the predicted P. falciparum incidence and prevalence. The strongest reduction was observed when three consecutive FSAT were implemented at the beginning of the low transmission season, and if malaria diagnosis was done with PCR. Repeated interventions for consecutive years (10 years with microscopy or 5 years with PCR), would allow reaching near to zero incidence and prevalence rates., Conclusions: The addition of FSAT interventions to PCD may enable to reach P. falciparum elimination levels in low endemic areas of the Amazon Region, yet the progression rates to those levels may vary substantially according to the operational criteria used for the intervention.
- Published
- 2015
- Full Text
- View/download PDF
41. Malaria inhibits surface expression of complement receptor 1 in monocytes/macrophages, causing decreased immune complex internalization.
- Author
-
Fernandez-Arias C, Lopez JP, Hernandez-Perez JN, Bautista-Ojeda MD, Branch O, and Rodriguez A
- Subjects
- Animals, Antigen-Antibody Complex blood, B-Lymphocytes immunology, B-Lymphocytes metabolism, Complement Activation immunology, Female, Glomerulonephritis complications, Glomerulonephritis immunology, Humans, Macrophage Activation immunology, Macrophages metabolism, Malaria complications, Mice, Monocytes metabolism, Phagocytosis immunology, Plasmodium falciparum immunology, Plasmodium vivax immunology, Receptors, Complement 3b metabolism, Spleen immunology, Spleen metabolism, Antigen-Antibody Complex immunology, Macrophages immunology, Malaria immunology, Monocytes immunology, Receptors, Complement 3b immunology
- Abstract
Complement receptor 1 (CR1) expressed on the surface of phagocytic cells binds complement-bound immune complexes (IC), playing an important role in the clearance of circulating IC. This receptor is critical to prevent accumulation of IC, which can contribute to inflammatory pathology. Accumulation of circulating IC is frequently observed during malaria, although the factors contributing to this accumulation are not clearly understood. We have observed that the surface expression of CR1 on monocytes/macrophages and B cells is strongly reduced in mice infected with Plasmodium yoelii, a rodent malaria model. Monocytes/macrophages from these infected mice present a specific inhibition of complement-mediated internalization of IC caused by the decreased CR1 expression. Accordingly, mice show accumulation of circulating IC and deposition of IC in the kidneys that inversely correlate with the decrease in CR1 surface expression. Our results indicate that malaria induces a significant decrease on surface CR1 expression in the monocyte/macrophage population that results in deficient internalization of IC by monocytes/macrophages. To determine whether this phenomenon is found in human malaria patients, we have analyzed 92 patients infected with either P. falciparum (22 patients) or P. vivax (70 patients) , the most prevalent human malaria parasites. The levels of surface CR1 on peripheral monocytes/macrophages and B cells of these patients show a significant decrease compared with uninfected control individuals in the same area. We propose that this decrease in CR1 plays an essential role in impaired IC clearance during malaria.
- Published
- 2013
- Full Text
- View/download PDF
42. Plasmodium falciparum-derived uric acid precipitates induce maturation of dendritic cells.
- Author
-
van de Hoef DL, Coppens I, Holowka T, Ben Mamoun C, Branch O, and Rodriguez A
- Subjects
- Cell Communication, Dendritic Cells metabolism, Dendritic Cells pathology, Erythrocytes metabolism, Erythrocytes parasitology, Fluorescent Antibody Technique, Humans, Inflammation metabolism, Inflammation parasitology, Lymphocyte Activation, Malaria, Falciparum metabolism, Malaria, Falciparum pathology, Microscopy, Immunoelectron, Dendritic Cells immunology, Erythrocytes immunology, Inflammation immunology, Malaria, Falciparum immunology, Plasmodium falciparum physiology, Uric Acid metabolism
- Abstract
Malaria is characterized by cyclical fevers and high levels of inflammation, and while an early inflammatory response contributes to parasite clearance, excessive and persistent inflammation can lead to severe forms of the disease. Here, we show that Plasmodium falciparum-infected erythrocytes contain uric acid precipitates in the cytoplasm of the parasitophorous vacuole, which are released when erythrocytes rupture. Uric acid precipitates are highly inflammatory molecules that are considered a danger signal for innate immunity and are the causative agent in gout. We determined that P. falciparum-derived uric acid precipitates induce maturation of human dendritic cells, increasing the expression of cell surface co-stimulatory molecules such as CD80 and CD86, while decreasing human leukocyte antigen-DR expression. In accordance with this, uric acid accounts for a significant proportion of the total stimulatory activity induced by parasite-infected erythrocytes. Moreover, the identification of uric acid precipitates in P. falciparum- and P. vivax-infected erythrocytes obtained directly from malaria patients underscores the in vivo and clinical relevance of our findings. Altogether, our data implicate uric acid precipitates as a potentially important contributor to the innate immune response to Plasmodium infection and may provide a novel target for adjunct therapies.
- Published
- 2013
- Full Text
- View/download PDF
43. Genetic diversity in merozoite surface protein-1 and 2 among Plasmodium falciparum isolates from malarious districts of tribal dominant state of Jharkhand, India.
- Author
-
Hussain MM, Sohail M, Kumar R, Branch OH, Adak T, and Raziuddin M
- Subjects
- Alleles, Amino Acid Sequence, Blood Specimen Collection methods, DNA, Protozoan genetics, Genetic Variation, Humans, India epidemiology, Malaria, Falciparum epidemiology, Malaria, Falciparum transmission, Molecular Sequence Data, Plasmodium falciparum isolation & purification, Polymerase Chain Reaction methods, Polymorphism, Genetic, Sequence Alignment, Sequence Analysis, DNA methods, Antigens, Protozoan genetics, Malaria, Falciparum parasitology, Merozoite Surface Protein 1 genetics, Plasmodium falciparum genetics, Protozoan Proteins genetics
- Abstract
Introduction: The genetic make-up of malaria parasite is potent for understanding the parasite virulence, designing antimalarial vaccine and evaluating the impact of malaria control measures. There is a paucity of information on genetic structure of Plasmodium falciparum in Jharkhand, India where malaria is rampant and this study aimed to establish molecular characterization of P. falciparum field isolates from Jharkhand measured with two highly polymorphic genetic markers, i.e. the merozoite surface proteins (MSPs) 1 and 2., Methods: The genetic diversity of P. falciparum population from low transmission area, Ranchi, Bokaro and Hazaribagh and highly malarious area, Latehar and Palamau districts of Jharkhand were evaluated by polymerase chain reaction-sequencing analyzing msp-1 and msp-2 genes to explore the genetic structure of parasite from this understudied region., Results: A total of 134 P. falciparum isolates were analyzed by polymorphic regions of msp-1 and msp-2 and classified according to prevalence of allelic families. The majority of patients from all the five sites had mean monoclonal infections of 67·1 and 60·4% of P. falciparum for msp-1 and msp-2, respectively, whereas, mean multiple genotypes of 32·8 and 39·5% for msp-1 and msp-2, respectively. Interestingly, we observed higher multiclonal infection in low transmission area as compared to highly malarious area in the case of msp-1 genotypes, whereas in msp-2 higher multiclonal infection was observed in highly malarious area compared to low transmission area. The overall multiplicities of infection of msp-1 and msp-2 were 1·38 and 1·39, respectively., Conclusion: This is the first report on molecular characterization of P. falciparum field isolates from Jharkhand. The genetic diversity and allelic distribution found in this study is somewhat similar to other reports from India and Southeast Asian countries. However, P. falciparum infection can be highly complex and diverse in these disease-endemic regions of Jharkhand, suggesting continual genetic mixing that could have significant implications for the use of antimalarial drugs and vaccines.
- Published
- 2011
- Full Text
- View/download PDF
44. How long do the short-term violent video game effects last?
- Author
-
Barlett C, Branch O, Rodeheffer C, and Harris R
- Subjects
- Adolescent, Analysis of Variance, Humans, Male, Reference Values, Time Factors, Young Adult, Affect, Aggression psychology, Arousal, Video Games psychology, Violence psychology
- Abstract
How long do the effects of the initial short-term increase in aggression and physiological arousal last after violent video game play? Study 1 (N=91) had participants complete pre- and postvideo game measures of aggressive thoughts, aggressive feelings, and heart rate. Then, participants completed Time 3 measures after 4 min or 9 min of delay. Study 2 employed a similar procedure, but had participants (N=91) complete the hot sauce paradigm to assess aggressive behavior after a 0, 5, or 10 min delay. First, results indicated that aggressive feelings, aggressive thoughts, aggressive behavior, and heart rate initially increased after violent video game play. Second, results of the delay condition revealed that the increase in aggressive feelings and aggressive thoughts lasted less than 4 min, whereas heart rate and aggressive behavior lasted 4-9 min., (Copyright 2009 Wiley-Liss, Inc.)
- Published
- 2009
- Full Text
- View/download PDF
45. Genetic diversity in the Block 2 region of the merozoite surface protein 1 (MSP-1) of Plasmodium falciparum: additional complexity and selection and convergence in fragment size polymorphism.
- Author
-
Takala SL, Escalante AA, Branch OH, Kariuki S, Biswas S, Chaiyaroj SC, and Lal AA
- Subjects
- Alleles, Animals, Base Sequence, Child, Gene Frequency, Geography, Humans, Infant, Newborn, Kenya epidemiology, Malaria, Falciparum genetics, Molecular Sequence Data, Protein Structure, Tertiary genetics, Sequence Homology, Nucleic Acid, Genetic Variation, Malaria, Falciparum epidemiology, Merozoite Surface Protein 1 genetics, Plasmodium falciparum genetics, Polymorphism, Genetic, Selection, Genetic
- Abstract
Fragment size in the Block 2 repetitive region of merozoite surface protein 1 (MSP1) has commonly been used as a molecular marker in studies of malaria transmission dynamics and host immunity in Plasmodium falciparum malaria. In this study, we further explore the genetic variation in MSP-1 Block 2 underlying potential problems faced while studying the immune responses elicited by this vaccine target and while using it as a molecular marker in epidemiologic investigations. We describe the distribution of a new Block 2 recombinant allele family in samples collected from western Kenya and other malarious regions of the world and provide evidence that this allele family is found worldwide and that all MR alleles most likely originated from a single recombination event. We test whether the number of tandem repeats (i.e. fragment size) can be considered neutral in an area of high transmission in western Kenya. In addition, we investigate the validity of the assumption that Block 2 alleles of the same size and allele family are identical by examining MSP1 Block 2 amino acid sequences obtained from full-length MSP-1 clones generated from infected Kenyan children and find that this assumption does not hold. We conclude that the worldwide presence of a new allele family, the effect of positive natural selection, and the lack of conserved amino acid motifs within alleles of the same size suggest a higher level of complexity that may hamper our ability to elucidate allele family specific immune responses elicited by this vaccine target and its overall use as genetic marker in other types of epidemiologic investigations.
- Published
- 2006
- Full Text
- View/download PDF
46. Clustered local transmission and asymptomatic Plasmodium falciparum and Plasmodium vivax malaria infections in a recently emerged, hypoendemic Peruvian Amazon community.
- Author
-
Branch O, Casapia WM, Gamboa DV, Hernandez JN, Alava FF, Roncal N, Alvarez E, Perez EJ, and Gotuzzo E
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Animals, Anopheles parasitology, Antimalarials therapeutic use, Child, Child, Preschool, Female, Humans, Incidence, Infant, Malaria, Falciparum diagnosis, Malaria, Falciparum drug therapy, Malaria, Vivax drug therapy, Male, Middle Aged, Peru epidemiology, Plasmodium falciparum isolation & purification, Plasmodium vivax isolation & purification, Prevalence, Suburban Population, Time Factors, Malaria, Falciparum epidemiology, Malaria, Falciparum transmission, Malaria, Vivax diagnosis, Malaria, Vivax epidemiology, Malaria, Vivax transmission
- Abstract
Background: There is a low incidence of malaria in Iquitos, Peru, suburbs detected by passive case-detection. This low incidence might be attributable to infections clustered in some households/regions and/or undetected asymptomatic infections., Methods: Passive case-detection (PCD) during the malaria season (February-July) and an active case-detection (ACD) community-wide survey (March) surveyed 1,907 persons. Each month, April-July, 100-metre at-risk zones were defined by location of Plasmodium falciparum infections in the previous month. Longitudinal ACD and PCD (ACP+PCD) occurred within at-risk zones, where 137 houses (573 persons) were randomly selected as sentinels, each with one month of weekly active sampling. Entomological captures were conducted in the sentinel houses., Results: The PCD incidence was 0.03 P. falciparum and 0.22 Plasmodium vivax infections/person/malaria-season. However, the ACD+PCD prevalence was 0.13 and 0.39, respectively. One explanation for this 4.33 and 1.77-fold increase, respectively, was infection clustering within at-risk zones and contiguous households. Clustering makes PCD, generalized to the entire population, artificially low. Another attributable-factor was that only 41% and 24% of the P. falciparum and P. vivax infections were associated with fever and 80% of the asymptomatic infections had low-density or absent parasitaemias the following week. After accounting for asymptomatic infections, a 2.6-fold increase in ACD+PCD versus PCD was attributable to clustered transmission in at-risk zones., Conclusion: Even in low transmission, there are frequent highly-clustered asymptomatic infections, making PCD an inadequate measure of incidence. These findings support a strategy of concentrating ACD and insecticide campaigns in houses adjacent to houses were malaria was detected one month prior.
- Published
- 2005
- Full Text
- View/download PDF
47. Antibodies that inhibit binding of Plasmodium falciparum-infected erythrocytes to chondroitin sulfate A and to the C terminus of merozoite surface protein 1 correlate with reduced placental malaria in Cameroonian women.
- Author
-
Taylor DW, Zhou A, Marsillio LE, Thuita LW, Leke EB, Branch O, Gowda DC, Long C, and Leke RF
- Subjects
- Adult, Amino Acid Sequence, Animals, Cameroon, Case-Control Studies, Chondroitin Sulfates metabolism, Erythrocytes parasitology, Female, Humans, In Vitro Techniques, Malaria Vaccines immunology, Malaria, Falciparum parasitology, Merozoite Surface Protein 1 genetics, Merozoite Surface Protein 1 metabolism, Molecular Sequence Data, Plasmodium falciparum genetics, Plasmodium falciparum isolation & purification, Pregnancy, Pregnancy Complications, Parasitic parasitology, Antibodies, Protozoan blood, Malaria, Falciparum complications, Malaria, Falciparum immunology, Placenta parasitology, Plasmodium falciparum immunology, Pregnancy Complications, Parasitic immunology
- Abstract
Plasmodium falciparum-infected erythrocytes often sequester in the placenta of pregnant women, producing placental malaria, a condition that can compromise the health of the developing fetus. Scientists are hopeful that a vaccine can be developed to prevent this condition. Immunological mechanisms responsible for eliminating parasites from the placenta remain unclear, but antibodies to the carboxyl-terminal 19-kDa segment of the merozoite surface protein 1 (MSP1-19), the ring-infected erythrocyte surface antigen (RESA), and an erythrocyte-surface ligand that binds chondroitin sulfate A (CSA-L) have been implicated. In addition, antibodies to sporozoite and liver-stage antigens could reduce initial parasite burdens. This study sought to determine if antibodies to the circumsporozoite protein (CSP), liver-stage antigen 1 (LSA1), RESA, MSP1-19, or CSA-L correlated with either the absence of placental parasites or low placental parasitemias. Using a frequency-matched case-control study design, we compared antibody levels in women (gravidity 1 to 11) with and without placental malaria. Results showed that women who were antibody negative for MSP1-19 were at a higher risk of having placental malaria than women with antibodies (P < 0.007). Furthermore, an association between high levels of antibodies that blocked the binding of infected erythrocytes to CSA and low placental parasitemias was observed (P = 0.02). On the other hand, women with high antibody levels at term to CSP, LSA1, and RESA were more likely to have placental malaria than antibody-negative women. Since antibodies to MSP1-19 and CSA-L were associated with reduced placental malaria, both antigens show promise for inclusion in a vaccine for women of child-bearing age.
- Published
- 2004
- Full Text
- View/download PDF
48. Evidence for intragenic recombination in Plasmodium falciparum: identification of a novel allele family in block 2 of merozoite surface protein-1: Asembo Bay Area Cohort Project XIV.
- Author
-
Takala S, Branch O, Escalante AA, Kariuki S, Wootton J, and Lal AA
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Cloning, Molecular, Cohort Studies, Gene Amplification, Humans, Infant, Kenya, Malaria, Falciparum immunology, Merozoite Surface Protein 1 classification, Molecular Sequence Data, Sequence Alignment, Alleles, Genes, Protozoan genetics, Merozoite Surface Protein 1 genetics, Plasmodium falciparum genetics, Recombination, Genetic
- Abstract
We have investigated intragenic recombination in Block 2 of the merozoite surface protein-1 (MSP-1), where three allele-specific families: K1, Mad20, and RO33 were previously known. Using parasites from western Kenya, we have found a fourth Block 2 allele type, which is a recombinant between Mad20 and RO33 alleles. These recombinant alleles, which we have termed MR, contain sequence from the 5' region of Mad20 and the 3' region of RO33. The results of this study provide new data on the complexity of the MSP-1 antigen gene, which is a candidate vaccine antigen, and further support the importance of intragenic recombination in generating genetic variability in Plasmodium falciparum parasites in nature.
- Published
- 2002
- Full Text
- View/download PDF
49. Glycosylphosphatidylinositol anchors of Plasmodium falciparum: molecular characterization and naturally elicited antibody response that may provide immunity to malaria pathogenesis.
- Author
-
Naik RS, Branch OH, Woods AS, Vijaykumar M, Perkins DJ, Nahlen BL, Lal AA, Cotter RJ, Costello CE, Ockenhouse CF, Davidson EA, and Gowda DC
- Subjects
- Adult, Animals, Antibodies, Protozoan blood, Antibodies, Protozoan immunology, Carbohydrate Conformation, Carbohydrate Sequence, Cell Line, Child, Child, Preschool, Erythrocytes parasitology, Female, Glycosylphosphatidylinositols chemistry, Glycosylphosphatidylinositols isolation & purification, Humans, Immunity, Innate immunology, Infant, Macrophages cytology, Macrophages immunology, Macrophages parasitology, Malaria, Falciparum blood, Malaria, Falciparum parasitology, Malaria, Falciparum prevention & control, Male, Mice, Molecular Sequence Data, Plasmodium falciparum chemistry, Tumor Necrosis Factor-alpha metabolism, Glycosylphosphatidylinositols immunology, Malaria, Falciparum immunology, Plasmodium falciparum immunology
- Abstract
Induction of proinflammatory cytokine responses by glycosylphosphatidylinositols (GPIs) of intraerythrocytic Plasmodium falciparum is believed to contribute to malaria pathogenesis. In this study, we purified the GPIs of P. falciparum to homogeneity and determined their structures by biochemical degradations and mass spectrometry. The parasite GPIs differ from those of the host in that they contain palmitic (major) and myristic (minor) acids at C-2 of inositol, predominantly C18:0 and C18:1 at sn-1 and sn-2, respectively, and do not contain additional phosphoethanolamine substitution in their core glycan structures. The purified parasite GPIs can induce tumor necrosis factor alpha release from macrophages. We also report a new finding that adults who have resistance to clinical malaria contain high levels of persistent anti-GPI antibodies, whereas susceptible children lack or have low levels of short-lived antibody response. Individuals who were not exposed to the malaria parasite completely lack anti-GPI antibodies. Absence of a persistent anti-GPI antibody response correlated with malaria-specific anemia and fever, suggesting that anti-GPI antibodies provide protection against clinical malaria. The antibodies are mainly directed against the acylated phosphoinositol portion of GPIs. These results are likely to be valuable in studies aimed at the evaluation of chemically defined structures for toxicity versus immunogenicity with implications for the development of GPI-based therapies or vaccines.
- Published
- 2000
- Full Text
- View/download PDF
50. Anti-merozoite surface protein-1 19-kDa IgG in mother-infant pairs naturally exposed to Plasmodium falciparum: subclass analysis with age, exposure to asexual parasitemia, and protection against malaria. V. The Asembo Bay Cohort Project.
- Author
-
Branch OH, Oloo AJ, Nahlen BL, Kaslow D, and Lal AA
- Subjects
- Aging, Cohort Studies, Female, Humans, Immunoglobulin G classification, Infant, Infant, Newborn, Kenya epidemiology, Malaria, Falciparum epidemiology, Parasitemia epidemiology, Pregnancy, Regression Analysis, Seasons, Antibodies, Protozoan blood, Immunoglobulin G blood, Infectious Disease Transmission, Vertical, Malaria, Falciparum transmission, Parasitemia immunology, Pregnancy Complications, Parasitic
- Abstract
The anti-merozoite surface protein-1 19-kDa IgG (anti-MSP119KD) IgG responses of 33 parasitemic infants, aged 6-14 months, were compared with those of their mothers at the time of the infant's delivery and at the time the infants were sampled; the antimalaria protection associated with these responses was also compared. IgG1 and IgG3 were the predominant subclasses. Infants <300 days old and pregnant mothers had the lowest cytophilic-to-noncytophilic IgG ratio. By 300 days of age, the infants had IgG subclass compositions and levels similar to those of their mothers at the same date. Among infants, older infants with only 1 or 2 detected asexual parasitemias had the highest cytophilic-to-noncytophilic IgG ratio and IgG1 levels. IgG1 level was negatively correlated with protection. The findings suggest that the MSP119KD antibody response develops with age, not with multiple experiences with parasitemia, and, thus, that an antimalaria vaccine strategy for pregnant mothers could delay infants' first parasitemias until they are more capable of mounting a favorable anti-MSP119KD response.
- Published
- 2000
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.